The Tampa Bay Times reported that Scott had won the Senate seat, his third consecutive statewide election.

"Based on numerous media reports the U.S. Senate race has been called for Rick Scott. This obviously is not the result Senator Nelson and his campaign had worked so hard for. The Senator will be making a full statement tomorrow to thank all those who rallied to our cause," Nelson's spokesman said.

Nelson's loss Tuesday brings to an end to the Democrat's 18-year career in the U.S. Senate and signals that Florida, the nation's largest and most volatile swing state, isn't yet ready to say goodbye to its two-term governor.

Despite his alliance with Trump, Scott often kept the president at arm's length during his Senate — a tacit recognition that the president could prove politically toxic with moderate and Puerto Rican voters in the state, whom the Florida governor courted aggressively for months.

A wealthy former health-care executive, Scott has shown a willingness throughout his two gubernatorial campaigns and Senate bid to spend millions of his dollars of his personal fortune on his political ambitions.

The race was among the most competitive in the country, rated by The Cook Political Report as a "toss-up."

Note: This story originally reported that Nelson had conceded, as was reported by the Tampa Bay Times. A spokesman for Nelson clarified in a statement to The Hill that the senator had not conceded and will be making a statement later in the day.